Light Emitting Diodes

Lightning, Biological and Indicators

Transceivers, Receivers, Emitters

IR Sensors General Lighting Emitters Transceivers Optocoupler

Optocoupler

Optocoupler/Photocouplers consist of an infrared LED (emitting device) and a photosensitive receiving device optically coupled into the same package. What this does is allows electrical signals to be passed from the input to the output circuit; separated by an isolation barrier that is designed to withstand high voltage levels. It allows for the isolation of high and low-voltage components reliably. This finds its way into many applications for safety reasons, as well as to prevent the damaging of expensive or important electrical components.

Optocoupler Application Introduction

Package:SOP4, SOP5, SOP8, SOP16, DIP4, DIP6, DIP8, etc.

Devices:transistors, IGBT drive gate, TRIAC, etc.

Typical Reliability Tests

JEDEC MSL3 to MSL1, reflow@260°C
High-temperature storage: 150°C x 1000hrs
Temperature cycling: -55~125 °C x 1000 cycles
uHAST: 168hrs @130°C and 85%RH
Temperature humidity bias: 1000hrs @85°C, 85%RH, Vcc

Industrial Communication Buses

optocoupler application in smart meter system

Within the optocoupler market, industrial segment will remain the largest end use industry due to increasing demand for optocouplers in smart grid, smart meter, power supply industries.

Electrical Vehicle Charging System

optocoupler application in EV charging

Optocouplers in the automotive segment will witness the highest growth during the forecast period due to the increasing usage of optocouplers in hybrid and electric vehicles.

Encapsulation Solutions For Optocouplers

Typically, there are two types of packaging solutions for optocouplers using epoxy molding compound.

Type 1 - Double Mold | Outer Black And Inner White

double molding solutions for optocouplers

In this package, the inside white molding compound provides high light reflectance for planar structure and transmittance for single to pass through; the outer black epoxy molding compound largely improves the package reliability with moisture resistance and low thermal stress, compared with single mold design.

Key Material Considerations

Inner White

Light transmittance >25%@1mm
Dielectric voltage test (@6.3kV after 1hr@125°C PMC)
Anti-blue decay < 20% @125°C, 1000hrs
Bleed/Flash control, no wire sweep and voids

Outer Black

MSL3 precondition tests (125°C/4hrs bake, 3 x IR reflow@260°C)
Thermal cycling tests (-55~125°C, 300cycles)
PCT (2atm/121°C/100%RH)
Red ink penetration test (20mins immersion after PMC)

Type 2 - Single Mold | Outer White

Single molding solutions for optocouplers

The white molding compound with TiO2 pigment added brings high reflectivity. It reflects the light signals from LED to the detector as much as possible. Since it also works as outside protection, it needs to ensure the reliability of the devices.

Key Material Considerations

High light reflectance (>80%)
High thermal and humidity resistance
Anti-yellowing against heat and UV
Good adhesion to silicone
Good moldability, no flash/bleed, and wire sweep
Pass required reliability tests after MSL preconditioning

Product Recommendations

White, highly reflective epoxy molding compounds, also abreviated as WMC, are epoxy molding compounds that are filled with a highly reflective filler that stays reflective even after exposure to heat and UV for long periods of time. We offer a range of highly reflective, white, non-yellowing epoxy mold compounds for led packages and lighting applications that require a high-performance non-yellowing compound with high brightness and reflectivity. After the plant closing of KYOCERA in Singapore, a lot of customers are seeking for substitutes of Kyocera KE-96/KE-95

We are happy to say that we have developed multiple alternatives of GT-W170 Series to Kyocera KE-96/KE-95 with high reflectivity and you can contact us to request samples.

PROPERTY	KE-96A	KE-96A5	GT-W170-2	GT-W170-15	GT-W170-6
Epoxy Resin	OCN	OCN+Confidential	Multi-functional +BPA	OCN	Confidential
Hardner	PN	Confidential	Anhydride	PN	Confidential
Filler Content	78%	76%	70~75%	70~75%	70~75%
Filler Shape	Crush	Crush	Crush	Crush + Spherical	Crush
Specific Gravity	2.12	2.05	1.98	1.96	1.89
Light Reflectance 0.5mm @800nm	87~89%	75~79%	93%	91%	91%
Light Reflectance 0.5mm @940nm	89%	77%	92%	89%	90%
Reflectance & heat Resistance			◼︎◼︎◼︎◼︎	◼︎◻︎◻︎◻︎	◼︎◼︎◼︎◻︎
Moisture Resistance			◼︎◼︎◻︎◻︎	◼︎◼︎◼︎◻︎	◼︎◼︎◻︎◻︎
Molding Shrinkage & Stress			◼︎◼︎◼︎◻︎	◼︎◼︎◻︎◻︎	◼︎◼︎◻︎◻︎
Moldability			◼︎◼︎◼︎◻︎	◼︎◼︎◼︎◻	◼︎◼︎◻︎◻︎
Continuous Moldability			◼︎◼︎◻︎◻︎	◼︎◼︎◼︎◻︎	◼︎◼︎◻︎◻︎
Key Advantage			High whiteness High reflectance Oxidation-resist	High MSL Good moldability	Balanced performance

GT-W170 Reliability Test Results

GT-W170 series white reflective compound oxidation data after molding

Anti-yellowing Capability: W170-2 > W170-6 > W170-15

Reflectance Decay By Yellowing:

Wavelength > 700 nm: All the three samples show no obvious reflectance decrease by heat oxidation with PMC condition 175°C * 4 hrs
Wavelength < 650 nm: WMC170-15 has shown reflectance value drop, which means yellowish color by heat oxidation

GT-W170 white reflective compound yellowing images after molding

Yellowing Appearance:

WMC170-15: Only the surface contacting with air shows yellowish color, however, the inner material shows no color change.
WMC170-2: No color change by heat oxidation
WMC170-6: No color change by heat oxidation